The disclosed embodiments of the present invention relate to transmitting high-frequency signals, and more particularly, to a circuit device with a signal line transition element which passes signals through multiple layers of a multilayer circuit carrier and with impedance transformers electrically connected to signal terminals of the signal line transition element.
In a wireless network, the connectivity and communication between devices is achieved through antennas attached to receivers or transmitters in order to radiate the desired signals to or receive the desired signals from other elements of the wireless network. In radio communication systems, such as millimeter-wave radios, discrete components are usually assembled with low integration levels. These systems are often assembled using expensive and bulky waveguides and package-level or board-level microstrip structures to interconnect semiconductor elements and their required transmitter/receiver antennas. With recent progress in the semiconductor technology and packaging engineering, the dimensions of these radio communication systems become smaller and the integration of antennas with their radio-frequency (RF) front-end circuits becomes more desirable. For a specific application such as a wireless universal serial bus (USB) application, the operating distance is limited to about one meter, and a single antenna with about 7 dBi at 60 GHz will provide the necessary antenna gain. For one point-to-point application (such as a wireless video application) which has an operating distance as long as 10 meters or another point-to-point application (such as a radar application) which has an operating distance longer than 10 meters, an antenna gain as high as 30 dBi, depending on the actual application, is required. However, a high gain antenna generally has a very narrow beam width, so pointing the antenna is very difficult for consumers. Therefore, a radiation pattern steerable array (also called phased array) is necessary. For example, phased arrays are widely used in military radars. However, packaging an RF die with an integrated antenna or antenna array is extremely difficult and very expensive due to expensive components and extensive labor involved.
Thus, there is a need for an innovative assembly design of wireless communication elements.